Why is the conflict in the UK Labour Party described by some as the “chicken coup”?

In the current conflict in the UK Labour Party, some are using the phrase Chicken Coup:

Morning Star: Chicken Coup rebels are running out of room

David Graeber in The Guardian: As the rolling catastrophe of what’s already being called the “chicken coup” against the Labour leadership winds down,...

Weblog “Another angry voice”: The failed "chicken coup" demonstrates that the Blairites aren't even good at the stuff they used to be.

A Chicken coop is a building where female chickens are kept. A Coup d`état is the illegal and overt seizure of a state by the military or other elites within the state apparatus.

I can understand why Corbyn supporters may choose to use the word “Coup”, but why “Chicken coup”?

Solution 1:

According to Mike Sivier's blog:

The rebellion in the Parliamentary Labour Party has been labelled the #ChickenCoup on social media because, while its members are trying to mount a coup against Mr Corbyn, they are afraid of revealing their treachery to members of their own constituency parties, who support the Labour leader.

and coup I assume means both coup d'état and implies perhaps that Westminster is somewhat like a chicken-coop where MPs behave like (stupid) chickens.